From 1531a6a6b81a4e6f9eec9a5608758a6ea14b96e0 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Mon, 16 Mar 2009 17:04:57 -0700 Subject: [PATCH] x86, dmar: start with sane state while enabling dma and interrupt-remapping Impact: cleanup/sanitization Start from a sane state while enabling dma and interrupt-remapping, by clearing the previous recorded faults and disabling previously enabled queued invalidation and interrupt-remapping. Signed-off-by: Suresh Siddha Signed-off-by: H. Peter Anvin --- drivers/pci/dmar.c | 5 +---- drivers/pci/intel-iommu.c | 29 +++++++++++++++++++++++++++++ drivers/pci/intr_remapping.c | 17 +++++++++++++++++ include/linux/dmar.h | 2 ++ 4 files changed, 49 insertions(+), 4 deletions(-) diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index 932e5e3930f..f1805002e43 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -982,7 +982,7 @@ static int dmar_fault_do_one(struct intel_iommu *iommu, int type, } #define PRIMARY_FAULT_REG_LEN (16) -static irqreturn_t dmar_fault(int irq, void *dev_id) +irqreturn_t dmar_fault(int irq, void *dev_id) { struct intel_iommu *iommu = dev_id; int reg, fault_index; @@ -1074,9 +1074,6 @@ int dmar_set_interrupt(struct intel_iommu *iommu) return 0; } - /* Force fault register is cleared */ - dmar_fault(irq, iommu); - ret = request_irq(irq, dmar_fault, 0, iommu->name, iommu); if (ret) printk(KERN_ERR "IOMMU: can't request irq\n"); diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 25fc1df486b..ef167b8b047 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -1855,11 +1855,40 @@ static int __init init_dmars(void) } } + /* + * Start from the sane iommu hardware state. + */ for_each_drhd_unit(drhd) { if (drhd->ignored) continue; iommu = drhd->iommu; + + /* + * If the queued invalidation is already initialized by us + * (for example, while enabling interrupt-remapping) then + * we got the things already rolling from a sane state. + */ + if (iommu->qi) + continue; + + /* + * Clear any previous faults. + */ + dmar_fault(-1, iommu); + /* + * Disable queued invalidation if supported and already enabled + * before OS handover. + */ + dmar_disable_qi(iommu); + } + + for_each_drhd_unit(drhd) { + if (drhd->ignored) + continue; + + iommu = drhd->iommu; + if (dmar_enable_qi(iommu)) { /* * Queued Invalidate not enabled, use Register Based diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c index 0d202d73a1a..a84686b2478 100644 --- a/drivers/pci/intr_remapping.c +++ b/drivers/pci/intr_remapping.c @@ -499,6 +499,23 @@ int __init enable_intr_remapping(int eim) struct dmar_drhd_unit *drhd; int setup = 0; + for_each_drhd_unit(drhd) { + struct intel_iommu *iommu = drhd->iommu; + + /* + * Clear previous faults. + */ + dmar_fault(-1, iommu); + + /* + * Disable intr remapping and queued invalidation, if already + * enabled prior to OS handover. + */ + disable_intr_remapping(iommu); + + dmar_disable_qi(iommu); + } + /* * check for the Interrupt-remapping support */ diff --git a/include/linux/dmar.h b/include/linux/dmar.h index c7768330c11..8a035aec14a 100644 --- a/include/linux/dmar.h +++ b/include/linux/dmar.h @@ -24,6 +24,7 @@ #include #include #include +#include #if defined(CONFIG_DMAR) || defined(CONFIG_INTR_REMAP) struct intel_iommu; @@ -125,6 +126,7 @@ extern void dmar_msi_mask(unsigned int irq); extern void dmar_msi_read(int irq, struct msi_msg *msg); extern void dmar_msi_write(int irq, struct msi_msg *msg); extern int dmar_set_interrupt(struct intel_iommu *iommu); +extern irqreturn_t dmar_fault(int irq, void *dev_id); extern int arch_setup_dmar_msi(unsigned int irq); #ifdef CONFIG_DMAR -- 2.41.1